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Insulation and Weatherization Guide

Ce r t a i nTe e d

Fiber Glass Insulation


CertainTeed … Leading the way since 1904 Adding insulation to your home keeps year-round temperatures

more comfortable and consistent. Your HVAC system won’t have

to work as hard, reducing your monthly energy bills. But how

much will you really save? What about available rebates and

incentives? And what’s the best type of insulation for different

areas of your home?

Save money when you buy insulation by taking

advantage of the many rebates and incentives

offered by government agencies and utilities.

Find out what’s available to you and get the

forms you’ll need to claim your money.

Upgrading your home’s insulation can make a

real difference in your heating and cooling bills.

This calculator will help you find out how much

you could save.

To find out the recommended R-values for

different areas of your home that will improve

overall energy efficiency and reduce monthly

energy bills, simply select the state and county

where you live. The insulation calculator can also

help you determine the total square footage of

product that you’ll need for your project(s).

Go to: www.certainteed.com/itools

3certainteed.com/insulation — 800-233-8990

Table of ContentsThe Basics

2 Why Choose CertainTeed?

3 CertainTeed Insulation Product Line

4 Create a More Comfortable Home

6 Why You Should Insulate – The Benefits

7 Insulation – The Facts

8 8 Reasons Fiber Glass Is Preferred by Homeowners

9 Measuring Insulation’s Power – R-value

10 Recommended R-values

12 Moisture and Vapor Retarders

14 Why It’s Important to Ventilate

16 Areas in Your Home to Insulate

Installation

18 Estimating – How Much Insulation Will You Need?

19 Helpful Hints – Preparing to Install Insulation

20 Getting Started

20 The Supplies You'll Need

20 Tools and Equipment

20 Protective Gear

21 Installation Basics

21 Installing Faced Insulation with Stapling Flanges

22 Installing Unfaced Insulation

22 Vapor Retarder Installation Guidelines

24 Specific Insulation Projects

24 Adding Insulation to Under-Insulated Attics

25 Insulating Attics in New Homes

26 Cathedral Ceilings

26 Cantilevered Overhangs

27 Exterior Sidewalls

27 Narrow-Framed Cavities

28 Walls of Unheated Garages

28 Masonry Walls

28 Floors

30 Crawlspaces

30 Insulating at Bridging

31 Ducts and Pipes

Insulation, Weatherization and Home Performance

32 A Systems Approach

32 Sealing the Envelope

32 Windows and Doors

33 Heating and Cooling Equipment

33 Water Heaters


The Basics

Why Choose CertainTeed?Through the responsible development of innovative and

sustainable building products, CertainTeed has helped shape

the building products industry for more than 100 years.

Founded in 1904 as General Roofing Manufacturing Company,

the firm’s slogan “Quality Made Certain, Satisfaction

Guaranteed” quickly inspired the name CertainTeed. Today,

CertainTeed is North America’s leading brand of exterior and

interior building products, including roofing, siding, fence,

decking, railing, trim, insulation, gypsum and ceilings.

CertainTeed offers a complete line of insulation products,

including time-tested and trusted fiber glass batts, rolls and

blown-in insulation, innovative vapor retarder technology, and

highly regarded HVAC products and spray foam insulation.

All of CertainTeed’s insulation products can help building

professionals earn credits to meet environmentally conscious

construction standards like the U.S. Green Building Council’s

(USGBC) Leadership in Energy and Environmental Design

(LEED®) and the National Association of Home Builders’

(NAHB) National Green Building Standard.

CertainTeed insulation is GREENGUARD Gold

Certified and meets the most stringent standards

for very low volatile organic compound (VOC)

emissions, including formaldehyde.

ENERGY STAR® is a joint effort of

the U.S. Environmental Protection

Agency and the U.S. Department of

Energy. Its purpose is to encourage

the ongoing development of more energy-efficient products

and practices. CertainTeed fiber glass insulation products

meet ENERGY STAR requirements. For six consecutive

years, CertainTeed Corporation and our parent company,

Saint-Gobain, have received an ENERGY STAR Partner of the

Year award — fours years at the highest level of Sustained

Excellence. We were the first manufacturer of fiber glass

insulation to receive this honor.

2015


CertainTeed Standard Fiber Glass InsulationFiber glass insulation is a thermally and acoustically

efficient inorganic insulation solution for your entire home.

The lightweight flexibility of CertainTeed fiber glass makes

installation quick and easy. And because fiber glass is

inorganic , it’s noncombustible*, noncorrosive and will not

deteriorate or retain moisture.

CertainTeed standard fiber glass insulation is available in

batts and rolls, either unfaced or with kraft facing. A batt is a

pre-cut piece of insulation, usually 48" or 93" long. Standard

widths are available for 16" and 24" on-center spacing. Rolls are

available in lengths of 18' to 70'. CertainTeed SMARTBATT™ with

MoistureSense Technology™ is fiber glass insulation with an

integrated smart vapor retarder to help manage moisture.

CertainTeed Insulation Product Line

* Please note: Most vapor retarder facings attached to fiber glass insulation are flammable

and should not be left exposed. Standard facings should be installed behind, and in

substantial contact with, the back surface of wall or ceiling finish materials. Only unfaced

fiber glass insulation, or insulation with flame-resistant facings such as CertainTeed’s FSK

faced fiber glass insulation, can be left exposed.


Create a More Comfortable Home

Sealing air leaks stops unpleasant drafts and noise, while

helping ensure thermal performance. It creates a tighter

building envelope that influences every other aspect of a

comfortable home.

Air Tightness

Acoustics play an important role in a home’s overall comfort.

Insulation helps block disturbing outside noise and, when

added to interior walls, limits room-to-room noise.

Acoustics

Highly efficient fiber glass and spray foam insulation help

save on energy bills* and create a more comfortable

living space.

Thermal Performance

Your insulation choice impacts

thermal performance as well

as moisture management,

air tightness and acoustics.

It's important to choose wisely during a home's

construction, as upgrading later can be difficult and

expensive. When your insulation system successfully

controls all the following aspects, you can achieve a

higher level of Complete Comfort in your home.

An effective vapor retarder can reduce the risk of mold

and mildew, improving indoor air quality and helping

avoid potentially costly damage from rot.

Moisture Management

The Basics

* For more information, visit www.energystar.gov

Air Tightness

ThermalPerformance + Acoustics+Moisture

Management = Complete Comfort+


TrueComfort®

Adding attic insulation is easy with the TrueComfort system,

which comprises fiber glass blown-in insulation and the blowing

machine used to install it. The machine is portable and simple

to operate. The insulation is super-expanding, requiring fewer

bags than competing products to achieve the same R-value.

Do-it-yourselfers can rent the machine at a

local retailer or lumberyard to retrofit attics,

the area of the house where adding insulation

will usually have the most significant effect on

energy consumption and thus on energy bills.

TrueComfort is a good choice for attics that

have no insulation; it can also be installed

over existing insulation.

SMARTBATT™ Moisture is unavoidable and must be

managed in order to prevent condensation

within your walls. The average family of

four can generate up to three gallons of

internal moisture vapor in a home on a daily

basis. Without proper protection, this can

lead to mold and mildew growth in the wall

cavity. SMARTBATT with MoistureSense

Technology is a first-of-its-kind fiber glass

insulation batt that changes permeability

based on relative humidity, reducing the

potential for mold and mildew growth.

SMARTBATT effectively manages moisture

while addressing thermal comfort.

MemBrain™MemBrain Continuous Air Barrier and

Smart Vapor Retarder, is a patented

smart vapor retarder with MoistureSense

Technology that helps provide superior

moisture management needed in an airtight

envelope. MemBrain adapts its permeability

based on the humidity levels to help keep

wall cavities dry, preventing moisture vapor

from entering the cavity in the winter and

allowing moisture buildup to escape the

cavity in the summer.

SMARTBATT™

MemBrain™

TrueComfort®


The Basics

Why You Should Insulate – The BenefitsWithout adequate amounts of properly installed insulation, your

home loses heat in the winter and gains heat in the summer.

That can lead to higher energy bills and uncomfortable living

conditions. Insulation, which helps to control heat flow in your

home year-round, provides these benefits:

• Reduce energy costs. Insulation protects your home with a

thermal blanket that can help reduce costly energy loss. This

can help you save on fuel bills during both the heating and

cooling seasons.*

• Sound control. Noise in your home can be reduced by

strategically installing insulation to help absorb sound.

• More comfortable living environment. A well-insulated home

is a more comfortable home, room to room, loor to ceiling.

• Higher home resale value. By upgrading your home’s

insulation to optimum levels for your geographic region, you

can expect your home to increase in value at resale time.

• Conserves natural resources. If you increase the insulation

in your home, you will decrease the amount of energy used

to heat and cool it. That means fewer pollutants are released

into the atmosphere. It also means fewer power plants are

needed to produce energy to heat and cool your home –

which helps conserve natural resources. For every BTU used

to manufacture fiber glass insulation, on average 12 BTUs are

saved per year.

* Savings vary. To find out why, go to www.energystar.gov.

Higher R-values mean greater insulating power.


Insulation – The FactsThere are three main types of insulation materials commonly

used in homes today: fiber glass, polyurethane and cellulose.

Fiber Glass Fiber glass insulation is spun from molten

sand and recycled glass into fibers. It is

inorganic, naturally noncombustible and

will not deteriorate, settle over time or lose

its R-value.

Polyurethane

Polyurethane is a two-component water–

blown spray foam that comes in two

types – open cell and closed cell. Foam

provides thermal insulation for the interior

of buildings and reduces air infiltration

through the building envelope.

Cellulose

Cellulose is made from recycled

newspapers. Since it’s flammable, it must

be treated with chemicals (up to 20% by

weight) to reduce the risk of fire. Cellulose

can still burn when exposed to a heat

source, such as a light fixture.

Fiber glass

Polyurethane

Cellulose


The Basics

* Savings vary. To find out why, go to www.energystar.gov.

Higher R-values mean greater insulating power.

8 Reasons Fiber Glass is Preferred By HomeownersThese are the eight key reasons why fiber glass is clearly the

type of insulation most used and preferred by homeowners.

1. CertainTeed fiber glass is permanent. Fiber glass insulation

will last for the life of a home without losing its effectiveness.

It won’t settle or deteriorate over time.

2. CertainTeed fiber glass can help reduce energy costs.

A properly insulated home can reduce your energy costs

during the heating and cooling seasons.*

3. CertainTeed fiber glass won't retain moisture. Fiber glass

will not retain moisture. Other insulation products absorb and

hold moisture, which can result in permanent loss of R-value.

4. CertainTeed fiber glass provides sound control. Fiber glass

is an excellent acoustical material in interior and exterior

walls. Strategically placed, it can act as a sound barrier to

unwanted noise from appliances, stereos, TVs, running water

and ventilation systems. It’s perfect for master bedroom

suites, bathrooms, in-home offices and entertainment rooms.

5. CertainTeed fiber glass is noncombustible. Because it’s

inorganic, fiber glass insulation is noncombustible. However,

the vapor retarder on most faced insulation products is

lammable and should never be left exposed. For more

information on faced insulation, see pages 13-14.

6. CertainTeed fiber glass is proven to work in independent

tests. Its effectiveness in improving thermal performance has

been confirmed in third-party tests performed by the NAHB

Research Center, Inc.

Measuring Insulation’s Power – R-valueThermal insulation’s effectiveness is measured in R-value.

R stands for thermal resistance to heat flow. R-values reflect an

insulation’s ability to resist the flow of heat, out of your home in

the winter and into your home in the summer. The higher the

R-value, the greater the insulating power and the greater your

potential energy savings.

R-values are determined by thickness and density. For example,

two different insulation products can have an identical thickness

of 3-1/2", but because one product is much denser – has more

fibers per cubic inch – it has greater insulating power and a

higher R-value. CertainTeed manufactures three different 3-1/2"

products, R-11, R-13 and R-15.

Insulation R-values can be added together for a higher total

R-value. For example, two layers of R-19 insulation can be

stacked on top of each other to achieve a total R-value of R-38.


7. Fiber glass is safe. Fiber glass insulation is one of the most

tested building products in the world. Research into the health

aspects of fiber glass spans 50 years and tens of millions of

dollars. Fiber glass insulation is safe to manufacture and

install when simple, recommended work practices are

followed. You’ll find these practices outlined in this guide.

8. Renewable. Recycled. Fiber glass insulation is made of

rapidly renewable content (sand), a high percentage of

recycled glass and a plant-based binder.


The Basics

Recommended R-valuesUse the map and charts on this page with the house diagram

on page 16 to select the proper CertainTeed insulation product

for your specific do-it-yourself project.

Homes not insulated to today’s energy standards can

experience substantial heat loss in winter and heat gain in

summer. Installing the proper amount of thermally efficient

fiber glass insulation is one of the most cost-effective energy

conservation measures that can be taken.

Climate and fuel costs determine how much insulation should

be used for maximum economic return. As fuel and electric

costs increase, higher R-values are usually justified.

In many areas both heating and air-conditioning costs

contribute to the insulation recommendations shown here.

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IECC 2012 Thermal Requirements for Homes (R-values are installed minimums)

FLOOR R-VALUE

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BASEMENT a WALL R-VALUE

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CLIMATE

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a. “15/19” means R-15 continuous insulation on the interior or exterior of the home or R-19 cavity

insulation at the interior of the basement wall. “15/19” shall be permitted to be met with R-13

cavity insulation on the interior of the basement wall plus R-5 continuous insulation on the interior

or exterior of the home. “10/13” means R-10 continuous insulation on the interior or exterior of the

home or R-13 cavity insulation at the interior of the basement wall.

b. R-5 shall be added to the required slab edge R-values for heated slabs. Insulation depth shall be

the depth of the footing or 2 feet, whichever is less in Climate Zones 1 through 3 for heated slabs.

c. Basement wall insulation is not required in warm-humid locations as defined by Figure R301.1

and Table R301.1.

d. Or insulation sufficient to fill the framing cavity, R-19 minimum.

e. First value is cavity insulation, second is continuous insulation or insulated siding, so “13+5”

means R-13 cavity insulation plus R-5 continuous insulation or insulated siding. If structural

sheathing covers 40 percent or less of the exterior, continuous insulation R-value shall be

permitted to be reduced by no more than R-3 in the locations where structural sheathing is

used – to maintain a consistent total sheathing thickness.

f. The second R-value applies when more than half the insulation is on the interior of the mass wall.


The Basics

Moisture and Vapor Retarders

A vapor retarder is any material that limits the

transmission of water vapor. Every household

generates moisture, which is carried through

the air as water vapor. It’s generated by

everyday activities such as cooking, cleaning,

bathing and laundering. A family of four can

generate up to 2 to 3 gallons of water vapor in

a 24-hour period.

During the heating season, this water vapor

moves from a home’s warm interior to the

cooler exterior. If its passage into attics

and exterior walls isn’t slowed by a vapor

retarder, condensation can occur when the

vapor reaches a cold surface. Continued or

prolonged condensation can cause wood

rot and the growth of mildew and mold. And

when fiber glass insulation gets wet, it loses

some of its R-value until it dries. In warm,

humid regions with a long air conditioning

season and high exterior humidity, water

vapor sometimes moves in a continuous flow

from the warm exterior to the cooler interior of

the home.

Vapor retarders can be pre-attached to the

fiber glass insulation when you purchase it.

A vapor retarder can also be purchased

separately, then attached after installation of

unfaced insulation.

For years polyethylene sheeting has

been used with unfaced insulation when

a continuous, airtight vapor retarder film

was desired. However, polyethylene

does not allow excess moisture, which

MemBrain™

MemBrain™

blocks moisture

MemBrain™

releases moisture


can accumulate in a cavity, to escape. As a replacement,

CertainTeed recommends MemBrain™ Continuous Air Barrier

and Smart Vapor Retarder.

Other vapor retarders include special low perm paints,

plywood, waferboard, foil-faced polyisocyanurate, closed cell

polyurethane and 3/4" or thicker extruded polystyrene. All of

these, if properly installed with joints taped and holes or tears

repaired, are vapor retarders.

CertainTeed Fiber Glass Insulation is Available

in a Variety of Facings

Unfaced insulation is manufactured in a

variety of widths to insulate attics and to

allow pressure-fit installation in wall cavities.

This insulation is used with a separate

vapor retarder or when no vapor retarder

is required. The most common types of

separate vapor retarders used are made

from polyethylene or nylon , available in

several roll sizes. Separate vapor retarder

installation instructions are found in Vapor

Retarder Installation Guidelines on page 22.

Kraft faced insulation is manufactured with

a kraft paper vapor retarder attached.

The kraft paper is coated with a thin

layer of asphalt adhesive and the coated

side is applied to the unfaced fiber glass

insula tion material. The asphalt adhesive

bonds the kraft paper and the insulation

together. This type of insulation is used in

most parts of the country. It is flammable

and should never be left exposed. Most

types of kraft faced insulation have formed

stapling flanges at the edges for either

face or inset stapling.

Unfaced

Kraft faced


SMARTBATT™ with MoistureSense™ Technology is a first-of-

its-kind fiber glass insulation batt that changes permeability

based on relative humidity, helping to reduce the potential for

mold and mildew growth. SMARTBATT™

blocks moisture in the winter, and opens

enough for complete drying in the summer,

providing the highest level of moisture

management protection while addressing

thermal comfort.

Why It’s Important to VentilateSince vapor retarders (see pages 12-13)

work to retard the flow of water vapor from

inside homes into attics and wall cavities,

you should provide a way for the excess

moisture to escape to the outside. This is

done by providing adequate ventilation in

attics/flat ceilings and crawlspaces.

In the summer. Proper ventilation

prevents the attic from becoming a

hot-box that spills unwanted heat down

through the attic floor (even if the attic is

insulated) into the living area. This could

help reduce your air conditioning costs.

In the winter. Proper ventilation could help prevent moisture

from condensing on the insulation, rafters or roof deck.

Adequate ventilation creates a positive flow of air that allows

the house to “breathe” and helps prevent moisture from

damaging your attic and walls year-round.

The Basics

SMARTBATT™ faced


How to Ventilate Your Home

In an attic/flat ceiling. The most common ventilation method is

the natural or static ventilation system, which consists of simple

vent openings in your attic. Eave vents – openings under the

eaves – combined with roof or gable vents provide an effective

way to create positive movement of air out of the attic. Always

provide at least two vent openings for proper air flow. Air will

flow into one opening and out the other opening. Install attic

baffles to make sure insulation does not block eave vents.

As a general rule, you should provide one square foot of net

open vent area for each 150 square feet of attic floor when there

is no vapor retarder in the ceiling. If the ceiling has a vapor

retarder, provide one square foot of net open vent area for

each 300 square feet of attic floor area.

Ideally, 50% of the required ventilation should be provided

by vents located in the upper portion of your attic, with the

remaining 50% provided by eave vents.

If you’re planning to add insulation to your attic, it’s important

not to cover eave vent openings and to maintain a 1" space

between the insulation and roof sheathing so that air can move

freely from the eaves to the ridge or gable vents.

In a crawlspace. Providing at least two crawlspace vents will

allow a positive flow of air in and out of the crawlspace. One

square foot of free vent area is recommended for every 1,500

square feet of floor area covered with a polyethylene ground

cover. (In crawlspaces that are unheated or have a dirt floor, it

is recommended that the floor be covered with a polyethylene

vapor retarder.)

Cathedral ceilings. Cathedral ceilings are sloped ceilings

where insulation is installed in rafter spaces and the ceiling

finish layer is fastened directly to the rafters. In this type

of ceiling, a vented air space between insulation and roof

sheathing is usually recommended. CertainTeed manufactures

special high-density insulation for use in cathedral ceilings.

R-30C (cathedral) is 8-1/4" thick for use in 10" rafters and R-38C

(cathedral) is 10-1/4" thick for use in 12" rafters – this allows for a

1" air space above the insulation.


1. Attics and Ceilings

2. Exterior Walls

3. Interior Ceilings, Floors and Walls

4. Band Joists

5. Floors Over Unheated Spaces

6. Basement Walls

7. Crawlspaces

8. Cathedral Ceilings

9. Kneewalls

Areas in Your Home to Insulate

1

2

3

3

4

5 5

6

7

8

9

The Basics


The following list refers to locations shown in the diagram on

the left.

1. Attics, the most important area of a home to insulate.

Ceilings with cold spaces above; this includes dormer

ceilings.

2. Exterior walls. Sections that are sometimes overlooked are

walls between living spaces and unheated garages or

storage rooms, dormer walls, and the portions of walls above

ceilings of adjacent lower sections of split-level homes.

3. Interior ceilings, floors and walls where sound control

is desired.

4. Band or header joists, the wall section between loor levels.

5. Floors over unheated or open spaces such as garages and

porches. Floors over unheated basements. The cantilevered

portions of loors and under windows.

6. Basement walls.

7. Floors above vented crawlspaces. Insulation may also be

placed on crawlspace loors and walls.

8. Sloped walls and ceilings (cathedral ceilings) of attic

spaces finished as living quarters.

9. Kneewalls of attic spaces finished as living quarters.

Sound ControlThe key areas to insulate

are exterior and interior

sidewalls, ceiling/loor

assemblies and the

perimeter of any room

addition. Interior walls

are especially important

to insulate in order to

keep noise from traveling

between rooms.


Estimating – How Much Insulation Will You Need?Here’s an easy seven-step method for calculating the number of

insulation packages you’ll need to complete your project.

Step one: Measure the length and width (height, for walls) of the

area to be insulated.

Step two: Measure the length and height of door and window

openings for square footage that will NOT be insulated.

Step three: Length x Width (height, for walls) of the area to be

insulated – square footage of doors and windows that will NOT

be insulated = total square footage to be insulated.

Step four: Measure the distance between studs or joists to

determine the correct insulation width for the job. CertainTeed

insulation is available in a variety of sizes for 16" and 24"

on-center framing.

Step five: To compensate for joists or studs, use the following:

• For 16" – Total square footage to be insulated x .90 =

square feet of insulation

• For 24" – Total square footage to be insulated x .94 =

square feet of insulation

Note: When applying a second layer of insulation in the attic, lay the insulation across the

joists and do not compensate for joists.

Step six: Choose the appropriate recommended insulation

R-value for the area of the home that you’re insulating (refer to

the charts and diagram on pages 10-11 and 16).

Step seven: Square feet of insulation ÷ square footage listed on

one insulation package = total number of packages needed for

the job.

Installation


Helpful Hints – Preparing to Install Insulation• Because packaged insulation is highly compressed and

expands greatly when the wrapper is opened, leave insulation

in its wrapper until you’re ready to use it.

• For easier installation, use pre-cut batts

in walls and loors.

• Use continuous rolls in attics because of

larger spans.

• To cut insulation, lay it on a board with

the facing down, if applicable. Lay a

straightedge or 1" x 2" piece of lumber

over the area of insulation to be cut.

Press your straightedge down hard

and cut with a utility knife, using the

straightedge as a guide. Replace your

utility knife blade frequently for large jobs.

• Before you begin any insulation project,

make sure you minimize air infiltration

by caulking and sealing all top and

bottom plates, sealing any wires or open

penetrations, and weather stripping attic

access openings.

Opening the wrapper

Continuous roll insulation

Cutting insulation to size


Getting StartedThe Supplies You’ll NeedThe tools required for an insulating project vary depending on

the area of the house being insulated and the type of job – new

construction or retrofit. Some equipment, such as protective

gear, should be used with every job.

Tools and Equipment• Utility knife and extra blades

• Tape measure

• Straightedge for cutting the insulation (either metal or a piece

of wood like a 1" x 2")

• Stapler and staples (hand-squeeze or hammer type)

• Boards or sheets of plywood to place across joists when

kneeling in the attic (they can also be used as cutting

surfaces)

• Polyethylene or nylon sheeting if a separate vapor retarder is

needed

• Duct tape for sealing tears in the vapor retarder

• Long pole or broom handle for positioning pieces of

insulation near attic eaves

• Baffles if insulating near soffit vents

• Insulation supports (mesh screen or chicken wire, wire and

nails, or wire rods) for holding insulation up against floors

Protective Gear• Work gloves

• Protective glasses

• Disposable dust respirator – NIOSH rating of N95 or higher

• Long-sleeve shirt

• Cap or hard hart (a hard hat is recommended in the attic to

protect against protruding nails overhead)

Installation


Installation BasicsInstalling Faced Insulation

With Stapling FlangesThere are three commonly accepted methods of installing faced

insulation in wood framing members.

1. Inset stapling

• Place the insulation in the cavity and

check to be sure it completely fills the

cavity, top to bottom.

• Be sure that each piece is butted closely

to the next one before fastening. Gently

press the insulation at the sides into the

framing cavity, until the outside edge of

the stapling lange is lush with the face

of the framing.

• When inset stapling insulation between

inclined or vertical framing members,

start stapling at the top and work

down. Use enough staples to hold the

insulation firmly in place (approximately

every 8") and avoid gaps and fishmouths

between the langes and framing.

2. Face stapling (Not recommended where drywall will be glued to studs)

• Place the insulation between framing

members and check to be sure it fits the

cavity at both ends. With facing material

lush to the face of the framing , the langes will overlap the

framing. Staple the langes to the

face of the framing, using enough staples to hold the

insulation firmly in place (approximately every 8") to avoid

gaps and fishmouths.

• The lange of the faced insulation placed in the next cavity will

overlap the previously stapled lange. When more than one

piece is used, they must be snugly butted.

Inset stapling

Face stapling


3. Friction fit – no stapling

• CertainTeed offers a variety of products that do not require

stapling. These products are slightly wider and the additional

width keeps the insulation in place.

• To install faced products by friction fit,

gently place the insulation into the cavity

space between framing members. Make

sure the insulation facing is lush with the

face of the stud. The insulation must fit

snugly at the sides and ends.

• To install faced products that do not

have langes, such as Speedy R™, follow

the same instructions given below for

installing unfaced insulation.

Installing Unfaced InsulationTo install unfaced insulation, gently place

the insulation into the space between

framing members. It’s important that

insulation be correctly sized for the cavity

and fit snugly at the sides and ends.

Wherever batts or rolls of any type are too

short to fill a stud cavity, a piece should be

cut to size to fill the gap. When insulation is

too long, it should be cut to fit properly, not

doubled over or compressed.

Vapor Retarder Installation Guidelines• For most of the United States, vapor retarders should be

installed in exterior walls on the warm-in-winter side of the

insulation (toward the interior).

• For some warm and humid areas, such as Florida, the

Gulf Coast and Hawaii, vapor retarders should be installed

outside the building envelope. Check local building practice

and/or building codes to be sure. Continuously applied

low permeance vapor retarders, like polyethylene, are not

recommended because there may be times of high relative

humidity when the water vapor moves from the exterior

toward the interior. In these situations, a discontinuous vapor

retarder – such as kraft faced or SMARTBATT insulation – will

retard the passage of vapor from inside the home into framing

Unfaced insulation

Friction-fit insulation

Installation


cavities, yet allow walls to dry toward the interior when

needed. This helps prevent moisture buildup in the wall cavity

and decreases the potential for condensation.

• Vapor retarders are not a standard requirement for attics.

Except for very cold regions and in

isolated cases where there is high

humidity in the house during the winter,

attic vapor retarders aren’t required if

the attic has adequate ventilation. As a

rule of thumb, one square foot of vent

opening is needed for every 150 square

feet of ceiling area. See page 15 for more

information on ventilation.

• If installed in an attic, a continuous

vapor retarder also helps to reduce air

infiltration. If your home is built this way

– and a similar air infiltration retarder is installed in the exterior

walls – you should consider adding mechanical ventilation,

such as a heat recovery ventilator, to prevent trapping air

pollutants and moisture within the house. Moisture buildup

can cause mildew on the walls and ceilings.

• Never leave faced insulation exposed. The facings on

most insulation products will burn and must be installed in

substantial contact with an approved ceiling, wall or loor

construction material .

• Flame-resistant foil (FSK-25) is the only insulation facing that

can be left exposed.

• Separate vapor retarders are used in some constructions.

They should be installed toward the interior of the home. They

are available in many different roll sizes, and are installed by

stapling to the face of the framing. If more than one sheet is

required, a double fold should be made at the meeting of the

two pieces and stapled, or the sheets may be overlapped

and taped. The pieces, if stapled, should meet only at a stud

or a joist. Foil-backed gypsum board and special low perm

paints are also effective vapor retarders.

• Cover the vapor retarder with gypsum drywall or other

approved interior material, as required by local codes, as

soon as the insulation and vapor retarder have been installed.

Installing MemBrain™


Specific Insulation ProjectsWhenever insulation is installed, it’s very important that it fit

snugly on all sides. If the insulation is too long for a space, cut it

to the correct size. If it’s too short, cut a piece to fill the void.

Here are specific instructions and recommendations for various

do-it-yourself insulation projects. Be sure to carefully read

CertainTeed’s installation instructions printed on the packaging

of batt and roll insulation to be sure it’s properly installed.

Adding Insulation to Under-Insulated Attics• Measure the amount of insulation already in your attic. Check

the map and charts on pages 10-11 or your local building

codes for your area’s recommended R-values.

• Use unfaced insulation over existing insulation, bringing

the level of insulation between the loor joists up to the

top of the joists.

• Starting on one side of the attic, place unfaced insulation

perpendicularly across the top of joists and work toward

center. If necessary, push insulation under the eaves with a

broom handle or long stick. If the eaves overhang provides

ventilation, be careful not to block the vents.

• If you encounter pipes, beams or other obstructions, cut the

insulation to fit snugly around them.

• Do not cover lighting fixtures, exhaust fan motors or vents

protruding into the attic. Leave a 3" space between the

insulation and electric motors or lighting

fixtures. Only IC (Insulation Contact) rated

lighting fixtures may be covered or be in

direct contact with insulation.

• Attics that are used as living spaces

should be insulated. See the diagram on

page 16.

Installation

Insulating around

light fixtures


Insulating Attics in New Homes• Faced insulation should be used where no insulation exists

and where moisture condensation may occur. The vapor

retarder should be installed toward the interior of the home.

• Check the chart on pages 10-11 or your local building codes

for your area’s recommended R-values.

• Start installation on one side of the attic, place insulation in

between joists and work toward center. If necessary, push

insulation under eaves with a broom handle or long stick. If

the eaves overhang provides ventilation, be careful not to

block the vents.

• If you encounter pipes, beams or other obstructions, cut the

insulation to fit snugly around them.

• Do not cover lighting fixtures, exhaust fan motors or vents

protruding into the attic. Leave a 3" space between the

insulation and electric motors or lighting fixtures. IC rated

fixtures may be covered by insulation.

• Attics that are used as living spaces should be insulated.

See the diagram on page 16.

• If you’re adding a second layer of insulation, always use

unfaced insulation. Lay it across the joists and work from

eaves toward the center of the attic, butting insulation

against the wall at both ends.

Insulating an attic


Installation

Cathedral Ceilings As a general guideline, cathedral ceilings are insulated using the

same method as flat ceilings.

• The insulation should be stapled or held in place by pressure

against the sides of the rafters. An air space (at least 1")

between the insulation and roof sheathing, ventilated at the

ridge and soffit, is recommended.

• If using kraft faced insulation, the vapor retarder should be

installed toward the interior of the home. Start at the eaves

area and work toward the ridge. Make sure the batts are

snugly butted together.

• If using unfaced insulation, a separate vapor retarder should

be applied after the insulation is installed. Make sure the

vapor retarder is continuous. For more information on vapor

retarders, see pages 12-13.

• Fit the end of the batt snugly against the top plate at the

beginning of the cathedral ceiling framing.

• Working down the lange, staple about 8" apart until you

reach the end of the batt. Do this until the batts reach the

exterior walls. Fit batts tightly against each other.

• Cover the batts with an approved material such as gypsum

board. Do not leave exposed for an extended period of time.

Cantilevered Overhangs• Don’t overlook these areas. If the underside of the cantilever

has been closed, insulation must be installed by sliding

insulation into place from the room below.

Airflow in a cathedral ceiling


Exterior Sidewalls• Insulation should fit snugly against the framing on all sides.

Even the smallest openings between framing members

should be insulated.

• The vapor retarder should be installed toward the interior of

the house except in some warm and humid areas, such as

Florida, the Gulf Coast and Hawaii (see page 12).

• Fit the end of the batt snugly against the top piece of

framing. Working down, staple the langes, if attached, about

8" apart until you reach the bottom. Fit batts tightly against

the framing bottom.

• CertainTeed unfaced batts do not need stapling.

They should be installed in combination with foil-backed

gypsum board or polyethylene or

nylon film to provide optimum moisture

protection. The vapor retarder film

should cover framing members as well

as the insulation. Do not leave exposed.

Cover with an approved material such

as gypsum board.

Narrow-Framed Cavities• Insulate non-standard-width framed

spaces by cutting the insulation and

facing about an inch wider than the

space to be filled. Staple the uncut lange as usual. Pull the

facing on the cut side to the other stud and staple through the

vapor retarder to the stud.

• Clearances around fossil-fuel appliances should meet the

requirements of the National Fire Protection Association

(NFPA) or the appliance manufacturers’ recommendations.

Use only unfaced fiber glass insulation between wood

framing and masonry chimneys. Do not place insulation in air

spaces surrounding metal chimneys or fireplaces.


Installation

Walls of Unheated Garages• If the garage does not have studs, you will have to install

them before insulating. This is a relatively easy job. Place

studs 16" or 24" apart from the center of

one stud to the center of the next.

• Place insulation between studs with

vapor retarder toward the interior of the

home. Do not leave insulation exposed.

Cover with an approved material such as

gypsum board.

Masonry Walls• CertainTeed Masonry Wall Batts of

unfaced fiber glass are designed for

use behind paneling in masonry-type

construction.

• No stapling is necessary. Once the framing strips have been

applied, just fit batts between strips.

• Vapor retarders are not recommended for installation over

framing strips. Do not leave exposed. Cover with an approved

material such as gypsum board.

Floors • Install the insulation between loor joists and secure using

one of the following three methods to hold insulation

permanently in place: (a) Mesh screen or chicken wire can be

applied by stapling the wire to the bottom of the joists. Other

methods are to (b) lace wire back and forth around nails in

the bottom of the joists, or (c) use wire rods available at most

home centers.

Mesh screen or chicken wire: Use galvanized chicken wire,

nylon mesh or galvanized screen to hold the insulation in place.

After the insulation has been pushed into place, staple or nail

the mesh or screen to the joist faces.

Masonry wall installation


Wire lacing: Galvanized, malleable wire may be laced around

nails protruding from the faces of the joists or the wire may be

stapled to the joists. Space the wire and nails as needed to

prevent the insulation from sagging.

Wire rods: The easiest and most effective

way to hold insulation in place is to use

straight, rigid wire fasteners (preferably

galvanized), with pointed ends. Wire

fasteners are available for a variety of joist

spacing. Wedge the fasteners, which may

be used against wood, metal or concrete

and are slightly wider than the joist

spacing, by hand between the joists and

bowed upward so the insulation presses

gently against the subflooring. Space the

fasteners as needed to prevent the insulation from sagging

(usually 12" to 24" apart, and not more than 6" from the ends of

the batts and rolls).

• When insulating loors where the insulation is less than the

thickness of the joists and the method of installation does

not hold the insulation up against the sublooring, it will be

necessary to insulate the headers or band joists at outside

walls. This is because there will be an air space between the

top of the insulation and the subloor that will allow heat to be

lost at outside walls. It is recommended that the insulation

be pushed up to the subloor. If insulating over an unheated

area, the vapor retarder should be in substantial contact with

the subloor. Where the header is parallel with the loor joists,

it may be necessary to adhere insulation to the header or fill

the joist area with insulation.

• For homes on pilings where the underside of the loor is

exposed and readily accessible, the insulation should be

covered with a suitable exterior material to protect it from high

winds and physical abuse. Header and band joists should

also be insulated.

Holding insulation

with wire

• Place the insulation between the loor joists – start at one end

and work out. Insulation will stay in place temporarily. If faced

insulation is used, the vapor retarder should face toward the

heated area of the home.

• Be sure the ends of the batts fit snugly up against the band

joists, and the batt fits up lush against the bottom of the loor

to prevent loss of heat.

Crawlspaces• If your crawlspace has ducts or pipes, be sure to insulate

them. See Ducts and Pipes section on page 31 for more

information.

• An alternative approach to insulating ducts and pipes is to

simply insulate the entire wall. Measure lengths of insulation

from the top of the wall extending 2 feet along the ground.

Hold the insulation in place at the top by the sill using a

furring strip nailed over the insulation. The crawlspace

loor should be covered with a 4 to 6 mil polyethylene

vapor retarder.

Insulating at Bridging• Insulate bridging or cross bracing of ceiling or loor joists

by splitting a batt vertically at the center and packing one

half into the lower opening and the other half into the upper

opening. Another method is to butt the insulation to the

bridging, then fill the bridging space with scrap insulation.


Installation


Ducts and Pipes• Make sure your heating and air conditioning ducts are

insulated. If you have metal ducts, wrap them in fiber glass

insulation with a vapor retarder facing

to help reduce heating and cooling

costs. If you’re adding new ducts,

consider a high-efficiency fiber glass

duct system, which is made from rigid

fiber glass insulation boards formed

into ducts. A fiber glass duct system

thermally insulates as well as reduces

the noise from your heating/cooling unit

and noise from air travelling through the

duct system to the rooms in your home.

CertainTeed manufactures a full line of

fiber glass HVAC products for all types

of homes.

• Also make sure your pipes are wrapped

with insulation. This will reduce the loss

of heat from the hot water in the pipes.

Ultra*Duct™

Black Duct Board

Soft Touch™

Duct Wrap

A Systems ApproachFollowing are brief descriptions of steps you can take to ensure

that you get the most value for your insulation dollar, and other

ways to ensure that the elements of your home energy system

work together more effectively while consuming less.

Sealing the Envelope• If you think of your house as an envelope, seams, cracks and

other openings are rips in that envelope – and they need to be

sealed.

• An obvious area to focus on is cracks around windows and

doors. Using caulk and weatherstripping to seal these leaks

is one of the quickest and easiest ways to lower heating and

cooling bills.

• Less obvious but just as important are places

where plumbing, ductwork or electrical wiring

penetrates through walls, loors, ceilings and

soffits over cabinets. Narrower openings can

be sealed with caulk; if the hole is larger, small

pieces of standard fiber glass insulation, cut

to fit snugly into the space, will help solve the

problem. CertainTeed Handi-Fill™ is a multi-

purpose fiber glass roll that is conveniently

sized for these types of odd-sized jobs.

Windows and Doors• In many homes, windows and doors are the leading culprits

when it comes to the loss of conditioned air. Standard

windows and doors can lose approximately five to eight

times more energy than an insulated wall area of the same

size, while leaky windows alone can account for 10% to 25%

of your heating bill.

• Storm windows and doors are one way to help reduce energy

loss. Even more effective are double- or triple-pane windows

with high-performance glass (e.g., low-e glass). These

windows have two or three pieces of glass fused together


Insulation, Weatherization and Home Performance


around the edges, with the space in between filled with air

or inert gas. Double-paned glass windows offer double the

thermal efficiency of single-pane windows; triple-paned

windows provide three times the efficiency.

Heating and Cooling Equipment• The efficiency of a central heating and cooling system has

a major effect on energy consumption. It’s a good idea to have

your system tested by a professional, especially if it’s older.

• The thermostat is another aspect of the space conditioning

system that should be evaluated. Installing an automatic

setback thermostat will cut energy costs by automatically

adjusting the home temperature to relect your family’s

schedule. For example, the thermostat can be programmed

to move to a lower temperature during winter days when

no one is home, preventing the heater from running

unnecessarily.

Water Heaters• Heating water for showers, laundry and dishwashing can

account for about 15% of the typical utility bill. Ways to

reduce this usage include simply using less hot water, turning

down the thermostat on the unit, and buying a new, more

efficient model.

• Wrapping the water heater in a fiber glass insulation blanket

is another step you can take to save energy. An insulated

water heater can retain as much as 5% to 12% of the energy

that would otherwise be lost. When insulating an electric

water heater, be careful not to cover the unit’s thermostat;

if your unit is warmed by natural gas or oil, do not cover the

top, bottom, thermostat or burner compartment.

Insulation

For every insulation challenge,

there’s a CertainTeed solution.

Residential Sustainable Insulation®

CertaPro® Commercial Insulation

Machine WorksSpray Foam Insulation

HVAC / Mechanical

Air & Moisture Management

Premium Blow-in Insulation

2015

That’s confidence worth building on.™

CertainTeed Corporation

20 Moores Road

Malvern, PA 19355

Professional: 800-233-8990

Consumer: 800-782-8777

www.certainteed.com

ASK ABOUT ALL OF OUR OTHER CERTAINTEED® PRODUCTS AND SYSTEMS:

ROOFING • SIDING • TRIM • DECKING • RAILING • FENCE

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